Growth and Characterization of GaN on Si (111) Using AlN/α-Si{sub}3N{sub}4 Buffer structure

摘要

In this study, a novel AlN/α-Si{sub}3N{sub}4 buffer structure is introduced for the growth of thick crack-free GaN on Si(111). The 5:4 coincident lattice in AlN/α-Si{sub}3N{sub}4/Si(111) structure is correlated to the reduction of tensile stress in the AlN and GaN epilayers. Effective reduction of the lattice mismatch and stress in GaN/AlN/α-Si{sub}3N{sub}4/Si structure can alleviate the cracking problem in the thick GaN layer. As a result, a crack-free surface of 2 μ m GaN epilayer grown on Si(111) was demonstrated by using the AlN/α-Si{sub}3N{sub}4 buffer structure. The full widths at half-maximum (FWHM) values of the X-ray rocking curve and neutral-donor-bound exciton (D°X) are 1012 arcsec and 30 meV, respectively.